We are also dealing with this issue. It seems to happen when the memory of the application starts to float at a level close to ~2GB (not a perfect metric, obviously depends on the phone and other factors). I found it happened consistently for us when we had a memory leak, and was able to be reconciled by really profiling the app, and making sure all memory is freed before performing another user scan.

We've recently started seeing this exception as well. Did you ever find the root cause?